Refraction Image Effect starting point

[sticklez]

Wondering if there was any suggestion for an Refraction Image (post) Effect- I am having a hard time figuring out how to make the simple one work with the Template, specifically the grab pass with the screen

I also saw this which is somewhat similar but it is just a normal shader going through the UI, and wondering if that is the correct approach?
viewtopic.php?f=23&t=589&p=2466&hilit=rain#p2466

NM, figured it out, was just blending it wrong w/ screen